The role of hormone receptors in development and puberty

The development of radionuclide labelling of hormones has greatly facilitated the study of their interactions with their receptor sites in target tissues. Although in virtually all cases the real nature of the receptor site is unknown, nevertheless it is possible to study hormone\p=m-\receptor interactions qualitatively and quantitatively. This paper is devoted to some recent studies of steroid\p=m- \ and gon-adotrophin\p=m-\receptor reactions in central and peripheral tissues during development, mainly in rodents. The available evidence has been organized to examine what part these receptors may play in the attainment of sexual maturity. Steroid hormone receptors The evidence for steroid hormone receptors has been reviewed extensively (Thomas, 1973; King & Mainwaring, 1974; Gorski & Gannon, 1976). It is currently believed that the steroid penetrates the cell membrane and is bound tightly but reversibly to a cytoplasmic receptor protein. The activated complex moves to the nucleus and gene expression is modified. The early ontogenetic studies of androgen and oestrogen receptors in various tissues of the rat have been reviewed (Eisenfeld, 1972). In summary, cytoplasmic oestrogen receptors appear to be present in rat uterus and pituitary from the earliest age studied (Day 1 after birth). The uterin